Rotary pump.



" T. 1. PAGEL.

ROTARY PUMP.

APPLICATION FILED MAR. 28, I911.

Patented Jan. 1, 1918.

3 SHEETS-SHEET I.

TJ PAGEL T. J. PAGEL.

ROTARY PUMP. APPLICATION FILED mm. 28. 1'91]:

5 Q 8 TH E m h dm [II J I! m -w U G. R.

T. 1. PAGE L. ROTARY PUMP.'

' APPLICATION FILED MAR. 28. I911- Patented Jan. 1,1918,

' a SHEETSSHEET THEODORE J. PAGEL, F MINNEAPOLIS, MINNESOTL' no ranxPimr.

Specification of Letter: Pate n Patented Jan. 1, 1918.

Application filed March 28,1917. Serial No. 157,909.

To all whom it may concern:

Be it known that I, Tnnononn J. PAGEL, a citizen of the United States,residing at Minneapolis, in the county of Hennepin and State ofMinnesota, have invented certain new and useful Improvements in RotaryPumps; and I do hereby declare the following to me full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My present invention relates to rotary pumps and is in the nature of arefinement of, or improvementon, the pum disclosed and broadly claimedin my prior atent No. 1,085,290, of date, January 27, 1914. Gen"- erallstated, the invention consists of the nove devices and combinations ofdevices hereinafter described and defined in the claims. l a

In the accompanying drawings which illustrate the invention, likecharacters indicate like parts throughout the several views. l

Referring to the drawings:

Figure l'is a plan view ofthe improved pump,'some parts being brokenaway.

. Fig. 2 is a vertical section taken on the line 2-2 of Fig. 1, thebase'of the ump being shown in full, and some parts eing broken away;and

Fig. 3is a transverse section taken through the ump onthe line 33 ofFig. 2.

T e main case of the ump is preferably made up 'of an intermediatesection 4 and head; plates 5, bolted, or otherwise, rigidly securedthereto, with water-tight joints.-

The intermediate or body member 4 is formed with intersectingcylindrical piston chambers 6, which, at their upper portions, areseparated by a, ga tubular dome 8, the en s of which are open and areadapted to be connectedto discharge pipes,-not shown. Thejga 7 andpocket 9 afford an exhaust port which ermits the water to be dischargedlatera ly in btith directions as well asiradially' outward, all

admission portdlO of eculiar construction and the form of -whic will behereinafter .more fully considered, In the preferred ,construction, thepum secured on a tubular ase casting 11, the

1 containing packin 7 that leads to a pear. u

casing is rigidly ends of which, as shown are open for the intake ofwater, or other liquid to be pumped.

In line with the axes of the intersecting piston chambers 6, the headplates 5 are formed with outstanding stufling boxes 12 13 subject toscrewthreaded glands 1 which latter surround and closely engage sleeves15, preferably of bronze and which are shrunk, driven, or otherwiserigidly secured. on transversely extended piston shafts 16. These pistonshafts 16 are, as shown, mounted in-ball bearings 17 of any suitableconstruction, mounted in'bearing hubs 18 shown as cast integral with thehead plates 5, bein connected thereto by suitable flanges an ribs.

The head plates 5, from points below the stufling boxes 12 and above theintake ports 19, so that the said base'casting 11 is in constantcommunication with bothof the lateral admission or intake ports 10 fromend to end thereof.

Atone end, the piston shafts 16 are rovided with intermeshing spur gears2 .of the same diameter, and one of the said shafts, at its oppositeends is shown as provided with a spur ar 21 rom which power maybetransmitte to the ump. The gears 20 are shown as incased y a housing22 detachabl .secured to the hub 18 of the adjacent ed plate andadapting the said gears 20 to be run in oil. Y 7

Working in the'in-tersecting cylindrical piston chambers 6 and secured,one to each of the piston shafts 16' are rotary gear-like pistons 23,each of which, as shown, has four main teeth or fluid propelling lugs 24and four intervening tooth cavities 25.- Of course, the numberofpropellin teeth and tooth cavities may be varied; t least one e basecastsurface of each propelling tooth' 24 is prefslightly beyond saidpitch circles by luglike portions 26; that are arranged to engagecorresponding but reverse de ressions 27 of the cooperatln pistons. hecontacting extremities of t e lugs 26 are so circumferentiallyspacedthat they will closely engage an intermeshing tooth 24approximately on the pitch line thereof, when the said tooth is turnedclosely to the vicinit of a straight line intersectin the axes of t etwo pistons (see particularly Fig. 2). Here it may be noted that thelower lines of the dischar e ports or pockets 9 are separated from t eupper extremities. of the intake orts 10 by bridge siirfaces 28 that areslig itly wider than the maximum width of any one of the said toothcavities 25, so that no tooth cav 1ty can at any time form a directconnection between the said intake and discharge ports. The saidpropelling teeth or lugs 24 are rovided with suitable packing strips orla des 29.

The peculiar form of intake orts 10 may now be considered, and it will'e noted that the extremities thereof, are curved and are concentric tothe axis of the respective rotary pistons, and furthermore, it will beobserved that the curved outer lines thereof follow approximately thepitch lines of the two rotary pistons. With this arrangement,

the tooth cavities, in passing the said curved extremities, lie almostwholly radially in- .ward of the outer lines of said intake portswhileoonsiderable portions of the propelling teeth .lieradially outwardof the outer lines of said intake ports. These long extensions of theintake port, under rotation of the rotary pistons 1n the direction ofthe arrow marked thereon in Fig. 2, ive a relatively long interval oftime for t e tooth cavities and-the space between the propelling teethto be completely filled with water. The said arrangement also introducesthe water first.

to the more slowly moving radiall inner portions of the propelling. lugs24 o the rotary pistons and permits the water to be thrown graduallyradially outward and into" contact with the surrounding c lindricalwalls of the piston chambers, an this not only reduces strainon theparts by eliminat in'g water impact, but insures the operation of thepump at full capacity.

. Giving still closer attention 'to said lateral intake ports 10, itwill be seen that they extend from the plane of the intermediateconnection of said piston chambers along the opposite lines of travel ofthe teeth of the respective pistons, an that they have a total length,greater than ouble the depth of the deepest tooth cavity measuredradially"inward from the pitch line; and it may be also noted that saidintake ports. extend to points beyond two parallel planes intersectingthe respective axes ofthe two pistons, at right angles to a common planethrough said, axes;

which separate the intake and discharge ports.

In this same connection, it should be recalled that the matching mouthsof the base casting ll and the outwardly curved base flanges 19 of thehead plates 5 are much Wider than the piston chambers 6, and are of suchlongitudinal extent as. to be in communication with the lateral intakeports 10, from end to end of said ports, as best shown in Figs. 2 and 3.I

The said positions, extent and'relations of said intake ports 10, in theopposite walls of the cylinders 'orpiston chambers 6, relative to thetravel lines of the piston teeth, relative to the bridges 28, andrelative to the supply from the base castin 11 through sald lon matchingmonths 0 said casting 11 and t e outwardly and downwardly extendingflanges 19 of the face plate 5, of greater width than the chambers 6 andof a length equal to the intake ports, constitute hig ly serviceableimprovements over the structure disclosed inmy prior patent and over theentireprior art, so far as known .to me.

In respect to. the said bridges or bridge surfaces, 28, which separatethe lateral in-. take ports from the lateral discharge ports,

it may be seen, by reference to Fig. 2, that axes of the piston, asshown in Fig. 2.

By inspection of Fig. 2, it will also be Seen that I cut away orreducefthe rear sides of the pro elling teeth 24, as shown by the line30. his detail is of importance, when considered in its relationsto 'theteeth cavities 25, the lugs 26, lug seats or depressions 27, the lateralexhaust ports afiorded by the gap 7 and recesses 9, and the bridges 28,wit out lap on the pressure'or exhaust Side; for the reason that therebya large amount of clearanceis afi'orded, both for the radial and lateralesca e "of the water from between the teeth an teeth cavities, and whichcontinues so longor so late, as to prevent the caging of any but anextremely small'amount of water in the" interdental space between one ofthe teeth 24' and one of the cavities 25, at the time of the cut-"o'fl',or as the parts are shown in Fig. 2. In other through the axes of thetwo pistons. The

tOOLh cavity 25 is deeper than the tooth which intermeshes therewith,and "is' also wider thanthe said tooth, inward of the pitch line of thecavity, thereby afi'ording an abundance of clearance for this little b1tof" caged water, and which clearance remains practically constant,throughout the further movement of the intermeshing parts, untll theybegin to unmesh or open on the suction side of the bridges. Hence, therecan be no compressing action on this little bit of caged Water, at anytime, and no water-lock can possibly be produced, but, on the contrary,

the water simply passes from one side to the shown in Fig. 2, that noappreciable vacuum,-

and hence, no appreciable drag can be produced. In fact, the saidintermeshing parts begin to separate, at the lower pitch lines, almostco-incidently with the cut-oif from the exhaust at their upper pitchlines, there by affording a slight opening between the lower surfaces,shown in contact in Fig. 2, and thence through the adjacent notch 27 ofthe left hand piston into the suction chamber; and hence, there ispractically no vacaum ever produced and no drag whatever occurs. a

It should be noted that the reduced or cutaway portion of the back ofthe tooth 24, shown by the line 30, does not extend inward quite to thepitch line, and it must not do so,

because when the intermeshing teeth and teeth cavities are in theircentral positions on line with the axes of the piston shafts, as shownin Fig. 2, both sides of the teeth and teeth cavities should be incontact on said pitch line.

I have further observed, in practice, that sometimes yvhen rotarypistons of the above character are driven at overspeed, or when thewater is pumped from considerable depth, the water cavities of therotary pis tons will not be completely filled and partial I vacuum willbe formed therein. When this happens, and the incompletely filled watercavities of the pistons are turned into com munication with the exhaustor high pressure side, said partial vacuum Will produce more or lesssevere water hammer. This water hammer, of course, is not onl annoyowater outlet side of the exhaust ports,

pump ever produced, so far as I back to the intermediate portions of thepiston chambers. These by-passages, as shown,

are formed by small pi es 31 that connect ducts 32 of the piston cambers with ducts 33 of the outlet 8. The said pipes 31 are providedwith valves 34 by means of which they may be closed or opened toany'desired extent. The said ducts 32 must belocated at pointsintermediate the intake cut-01f and the opening to exhaust. The ducts 33may be located anywhere in the exhaust or discharge passages, such as inthe walls of the gap 7, the pockets9, or the discharges in the dome 8With this arrangement, ,under rotation of the propelling wheels, in thedirection stated, when the cavities of the rotary pistons which containpartial vacuum are turned into communication with the ports 32, waterunder high pressure from the outlet 8 will be forced throughthe saidpipes 31 and, by supplying the necessary water, will relieve the samefrom partial vacuum. In this way, the

(water hammer is prevented. When not required, said pipes 31 may, ofcourse, be closed, and hence, entirely out out of action. The deviceherein described is a rotary pump but it will, of course, be understoodthat with water supplied thereto under pressure, it would operate as ahighly eflicient rotary water motor. It will, therefore, be understoodthat'I do not herein limit myself to the use of the device as a pump.

My improved pump, herein disclosed,.has gone into extensive commercialuse and has attained a higher record for efiiciency in fire engine.service than any. other ear action now. What I claim is: L'Thecombination with a casing provided with interconnected piston chambers,of cooperating rotary toothed pistons working in said chambers, saidcasing having a suitable discharge port and having. in the oppositewalls of said piston chambers, at points past which the teeth of saidpistons sweep, ateral fluid intake'ports arranged to deliverthe fluid inopposite lateral directions, from said opposite ports, directly to thecavities between the teeth of said rotary pistons, said lateral fluidintake ports ex-.

tending from the plane of the intermediate connection of said pistonchambers along the greater than double the depth of the deepest toothcavity measured radially inward from the pitch line. p

2. The combination with a casing 'provided with interconnected pistonchambers, of coiiperating rotary toothed pistons working in saidchambers, said casing having a suitable discharge port and having, inthe opposite walls of said piston chambers at points past which theteeth of said pistons I sweep, lateral fluid intake ports arranged torating its discharge ports deliver the fluid in opposite lateraldirections, from'said opposite ports, directly to the cavities betweenthe teeth of said rotary pistons, said lateral-fiuid intake portsextending from the plane of the intermediate connection of said pistonchambersalon the opposite lines of travel of the teeth 0 the respectivepistons to points beyond two parallel planes intersecting the respectiveaxes of said two pistons at right angles to a common plane through saidaxes.

3. The combination with a casing having interconnected piston chambers,of cooperating rotary toothed pistons working in said chambers, saidcasing havi n rom its intake ports, and said intake ports being in theopposite side walls of said piston chambers at points past which theteeth of said pistons sweep and arranged to deliver the fluid inopposite lateral directions directly to the cavities between the teethof said. pistons and extending from the plane of the intermediateconnection of said piston chambers along the opposite lines of thetravel of the teeth of said respective pistons to points approximatelyopposite the ends of said bridges, substantially as described.

4. The combination with a casing having intersecting cylindrical pistonchambers provided with lateral intake and discharge ports and bridgesseparatingsaid intake and discharge ports, of cooperating rotary pistonswithin said chambers having coiiperating teeth and teeth cavitiesextending entirely across the peripheries of said pistons, the saidlateral intake ports extending from the plane of the intermediateconnection of said piston chambers along the opposite linesof travel ofthe teeth of respective pistons and located radially inward of the outerends of the piston teeth at points past which the teeth of said pistonssweep. r

5. The combination with a casing provided with intersecting cylindricalpiston chambers, of cooperating rotary pistons working within the saidchambers, the said pistons .having peripheral tooth members andcooperating tooth cavities arranged alternately and extending across theperiph-' ery of the said pistons to the side walls of the said pistonchambers, said casing having suitable discharge ports and oppositelateral intake ports, said intake ports having extensions following thesides of said pistons but located radially inward of the outerextremities of the tooth members thereof, the said tooth cavities beinglocated substantially inward of the outer lines of said port extensions.

6. The combination with a casing provided with intersecting cylindricalpiston chambers, of cooperating rotary pistons working withm saidchambers, said pistons bridges, sepa-' afford clearance ra ially outwardof theirv pitch lines, the said casing having intake and discharge portsthe said toothed members and toothed cavities, on both sides, havingclose engagement substantially on their pitch lines when turned to aline intersecting the axes of said pistons.

7. The combinationwith acasing having intersecting cylindrical pistonchambersprovided with lateral intake and discharge orts and bridgesseparating said intake an discharge ports, of cooperating rotary pistonsworking within said chambers and having cotiperating teeth and teethcavities extending entirely across the peripheries of said pistons,'saidteeth being cut away on their rear sides outward of their pitchlines and said bridges being substantially without lap on their exhaustsides and provided with lap on their intake sides, substantially asdescribed. p

8. The combination with a casing having intersecting cylindrical pistonchambers provided with lateral intake and discharge ports and bridgesseparating said intake and dison their rear sides outward of their pit'clines and said cotiperating teeth and teeth cavities being constructedand arranged to have close engagement substantially on their pitchlines, on both the exhaust and suction sides of said bridges, whenturned to a central line through the same and the axes of said twopistons, and said bridges being substantially without lap on theirexhaust sides and provided with lap on their intake sides, substantiallyas described.

9. The combination with a casing having intersecting cylindrical pistonchambers provided with intake and discharge ports, of cooperating rotarypistons working' within said chambers having cooperating teeth and teethcavities, the teeth being cut away on their rear sides and the cavitiesdeeper than the teeth and wider than the teeth inward of the pitch line,substantially as described.

10. The combination with a casing having intersecting cylindrical istonchambers provided with' lateral inta te ports and lateral teeth bein cutaway on their rear sides outward of their pitch lines, the said cavitiesbeing deeper than their cooperating teeth and" wider than said teethinward of the pitch line, said bridges being substantially without lapon their exhaust sides and provided with lap on their intake sides andsaid teeth and cavities being constructed and arranged to have closeengagement substantially on their pitch lines on the exhaust side, whenturned to .a central line through the same and the axes, of said twopistons, substantially as described. it

I 11. The combination with a casing provided with intersectingcylindrical piston chambers, of cooperating rotary pistons workingwithin the said chambers, the said pistons having peripheral toothmembers and cooperating tooth cavities arranged alternately andextending across the periphcry of the said pistons to the side walls ofthe said piston chambers, and by passages connecting the high pressuredischarge passage of said casing with portions of the respective pistonchambers intermediate the intake cut-ofl and the opening to exhaust.

12. The combination with a casing provided with intersecting cylindricalpiston chambers, of cooperating rotary pistons working within the saidchambers, the said pistons having peripheral tooth members andcooperating tooth cavities arranged alternately and extending across theperiph cry of the said pistons to the side walls of the said pistonchambers, and by-passages connecting the high pressure discharge pas:sage of said casing with portions of the rethe said lateral intake portsextending from the plane of the intermediate connection of said pistonchambers along the opposite lines of travel ofthe teeth of saidrespective pistons and located radially inward of the outer-ends of thepiston teeth at points past which the teeth of said pistons sweep andsaid chambers having peripheral walls which abut the main teeth of thepistons throughout the major portion of the travel thereof. In testimonywhereof I aiiix my signature in presence of two witnesses.

THEODORE J. PAGEL. Witnesses:

B. G. \Vnrrmm, F. D. MERCHANT.

